Generic vs. Name-Brand Levothyroxine

• Sponsor: Boston Children's Hospital (Other)
• Overall Status: Completed
• CT.gov ID: NCT00403390
• Collaborator: (none)
• Enrollment: 34
• Location: 1
• Arms: 2
• Duration (Months): 40
• Patients Per Site Per Month: 0.9

Study Details

Study Description

Brief Summary

This study compares two different brands of thyroxine (thyroid hormone). Currently, pharmacists may be substituting generic formulations of thyroid hormone without your doctor knowing about this. Although a small difference in thyroid function is not significant in most healthy children, adolescents and adults, in infants and toddlers even a small difference in thyroid function can have important harmful consequences on brain development. The purpose of the present study is to learn whether the difference between brands of thyroid hormone that are currently being substituted is sufficient to cause a difference in thyroid function.

Condition or Disease	Intervention/Treatment	Phase
Congenital Hypothyroidism; Hypothyroidism	Drug: Brand Name Levothyroxine (Synthroid); Drug: Generic formulation of Levothyroxine	N/A

Detailed Description

This study is an unblinded, randomized controlled cross-over study, which involves taking 2 different forms of levothyroxine sequentially over a 16 week period. Subjects will have a total of 3 visits over this time period. At the first visit, subjects are randomized to receive either generic (Sandoz) levothyroxine or Synthroid (Abbott) brand of levothyroxine. Blood is drawn for baseline thyroid function studies and other markers which are influenced by thyroid hormone at each visit. The second visit is the cross-over visit, and the final visit is a close-out visit, after which each subject will resume taking their previous formulation of levothyroxine.

Study Design

• Study Type: Interventional
• Actual Enrollment: 34 participants
• Allocation: Randomized
• Intervention Model: Crossover Assignment
• Masking: None (Open Label)
• Primary Purpose: Treatment
• Official Title: Generic vs. Name-Brand Levothyroxine: Assessment of Bioequivalence Using TSH as a Marker in Children With Permanent Hypothyroidism
• Study Start Date: Nov 1, 2006
• Actual Primary Completion Date: Dec 1, 2009
• Actual Study Completion Date: Mar 1, 2010

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Brand name levothyroxine (Synthroid) Dose previously demonstrated to normalize thyroid function given daily for 2 months	Drug: Brand Name Levothyroxine (Synthroid); Randomized crossover study using 8 weeks of brand name levothyroxine (Synthroid, manufactured by Abbott), then 8 weeks of the generic formulation of levothyroxine (manufactured by Sandoz). The dose of medication does not change throughout the duration of the study.; Other Names: Levothyroxine
Active Comparator: Generic formulation of Levothyroxine Dosage previously determined to normalize thyroid function given daily for 2 months	Drug: Generic formulation of Levothyroxine; Randomized crossover study using 8 weeks of the generic formulation of levothyroxine (manufactured by Abbott, then 8 weeks of brand name levothyroxine (Synthroid, manufactured by Abbott). The dose of medication does not change throughout the duration of the study.; Other Names: No other names

Outcome Measures

Primary Outcome Measures

1. Thyroid Stimulating Hormone as Primary Endpoint Measured at Initiation of Study, After 8 Weeks of One Drug, and Then 8 Weeks After the Second Drug. [3 points over 16 weeks]

Eligibility Criteria

Criteria

• Ages Eligible for Study: 3 Years to 18 Years
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes

Inclusion Criteria:

• Age between 3 and 18 years

• Diagnosis of Congenital Hypothyroidism with initial TSH > 100

• Ability to understand directions and follow all instructions

Exclusion Criteria:

• Not on any drug interfering with absorption of levothyroxine

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	Children's Hospital Boston	Boston	Massachusetts	United States	02115

Sponsors and Collaborators

• Boston Children's Hospital

Investigators

• Principal Investigator: Rosalind S Brown, MD, Boston Children's Hospital

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.

• Responsible Party: Jeremi Carswell, Principal Investigator, Boston Children's Hospital
• ClinicalTrials.gov Identifier: NCT00403390
• Other Study ID Numbers: 05-11-146
• First Posted: Nov 23, 2006
• Last Update Posted: Feb 23, 2018
• Last Verified: Jan 1, 2018

• Individual Participant Data (IPD) Sharing Statement: No
• Plan to Share IPD: No
• Additional relevant MeSH terms: Congenital Hypothyroidism; Hypothyroidism

Study Results

Participant Flow

Recruitment Details	Subjects were recruited through flyers in the endocrine clinic and letters with opt-out cards to contact. Recruitment started November 2006 and completed ended March 2010.
Pre-assignment Detail	Subjects' ages had to be between 3-18 years and had a diagnosis of hypothyroidism, either congenital or acquired with an initial TSH of >100 uIU/mL.

Arm/Group Title	Group 1	Group 2
Arm/Group Description	Branded Synthroid 8 weeks, then generic levothyroxine 8 weeks	Generic levothyroxine for 8 weeks then branded Synthroid for 8 weeks
Period Title: Overall Study
STARTED	16	18
COMPLETED	13	18
NOT COMPLETED	3	0

Baseline Characteristics

Arm/Group Title	Group 1	Group 2	Total
Arm/Group Description	Branded Synthroid 8 weeks, then generic levothyroxine 8 weeks	Generic levothyroxine 8 weeks, then branded Synthroid 8 weeks	Total of all reporting groups
Overall Participants	13	18	31
Age (Count of Participants)
<=18 years	13 100%	18 100%	31 100%
Between 18 and 65 years	0 0%	0 0%	0 0%
>=65 years	0 0%	0 0%	0 0%
Age (years) [Mean (Standard Deviation) ]
Mean (Standard Deviation) [years]	10 (1.2)	10 (1.0)	10 (1.1)
Sex: Female, Male (Count of Participants)
Female	9 69.2%	15 83.3%	24 77.4%
Male	4 30.8%	3 16.7%	7 22.6%
Region of Enrollment (participants) [Number]
United States	13 100%	18 100%	31 100%

Outcome Measures

1. Primary Outcome

Title	Thyroid Stimulating Hormone as Primary Endpoint Measured at Initiation of Study, After 8 Weeks of One Drug, and Then 8 Weeks After the Second Drug.
Time Frame	3 points over 16 weeks

Outcome Measure Data

Analysis Population Description

[Not Specified]

Arm/Group Title	Group 1	Group 2
Arm/Group Description	Branded Synthroid 8 weeks, then generic levothyroxine 8 weeks	Generic levothyroxine 8 weeks, then Branded Synthroid 8 weeks
Measure Participants	13	18
Baseline	2.455 (1.532)	2.131 (1.322)
After first drug	0.788 (0.631)	3.053 (1.233)
After second drug	3.112 (4.983)	1.217 (2.832)

Adverse Events

Arm/Group Title	Group 1		Group 2
Arm/Group Description	Crossover; Branded Synthroid 8 weeks, then generic levothyroxine 8 weeks		Crossover; Generic levothyroxine 8 weeks, then Branded Synthroid 8 weeks, then generic
All Cause Mortality
	Group 1		Group 2
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/13 (0%)		0/18 (0%)
Serious Adverse Events
	Group 1		Group 2
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/13 (0%)		0/18 (0%)
Other (Not Including Serious) Adverse Events
	Group 1		Group 2
	Affected / at Risk (%)	# Events	Affected / at Risk (%)	# Events
Total	0/13 (0%)		0/18 (0%)

Limitations/Caveats

Proof of principle study; small sample. Results may not be applicable to all populations.

More Information

Certain Agreements

All Principal Investigators ARE employed by the organization sponsoring the study.

There is NOT an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.